分辨率修改涉及两个概念：密度和尺寸
每个项目密度定义路径：
customize/customer_cfg/sp8810ga/res/system.prop
# 1 => add volume control in in-call screen
ro.sprd.volume_control_icon = 1
#LCD_Density for WGVA
ro.sf.lcd_density =240
dalvik.vm.heapsize=32m
ro.opengles.version=131072
搜索ro.sf.lcd_density关键字，
device/samsung/system.prop，vendor/sprd/hsdroid/system.prop
也有定义！
验证结果：
最终生成的build.prop文件
#LCD_Density for WVGA
ro.sf.lcd_density = 240
来自customize下的修改值！
手机目录system/build.prop通过adb导出来，
修改其中的值，再push进相应目录下的build.prop，重新开机，显示预先效果！
尺寸修改：
frameworks/base/core/java/android/content/res/CompatibilityInfo.java
publicstatic final int DEFAULT_PORTRAIT_WIDTH = 320;
publicstatic final int DEFAULT_PORTRAIT_HEIGHT = 480;
四组数据效果比较：
1)、正常效果：
DEFAULT_PORTRAIT_WIDTH = 320;DEFAULT_PORTRAIT_HEIGHT =480;ro.sf.lcd_density = 240;
2)、正常效果：
DEFAULT_PORTRAIT_WIDTH = 480;DEFAULT_PORTRAIT_HEIGHT =800;ro.sf.lcd_density = 240;
3)、界面显示正常，系列显示图标变小：
DEFAULT_PORTRAIT_WIDTH = 480;DEFAULT_PORTRAIT_HEIGHT =800;ro.sf.lcd_density = 160;
4)、部分界面显示不全(如锁)，系列显示图标变小：
DEFAULT_PORTRAIT_WIDTH = 320;DEFAULT_PORTRAIT_HEIGHT =480;ro.sf.lcd_density = 160;
结论：
ro.sf.lcd_density影响分辨率的关键因素，
目前四个等级的屏幕密度等级，
决定每个APK选取res下的不同资源文件。
如主流屏幕drawable-hdpi(密度240)、drawable-mdpi(密度160)等；
相关说明：
frameworks/base/core/java/android/util/DisplayMetrics.java
private static int getDeviceDensity() {
// qemu.sf.lcd_density can be used to overridero.sf.lcd_density
// when running in the emulator, allowing for dynamicconfigurations.
// The reason for this is that ro.sf.lcd_density is write-once andis
// set by the init process when it parses build.prop beforeanything else.
return SystemProperties.getInt("qemu.sf.lcd_density",
SystemProperties.getInt("ro.sf.lcd_density",DENSITY_DEFAULT));
}
frameworks/base/services/surfaceflinger/DisplayHardware/DisplayHardware.cpp
#
if(property_get("qemu.sf.lcd_density", property, NULL)<= 0) {
if (property_get("ro.sf.lcd_density", property, NULL)<= 0) {
LOGW("ro.sf.lcd_density not defined, using 160 dpi bydefault.");
strcpy(property, "160");
}
} else{
# mDpiX = mDpiY = atoi(property);
}
上面表示：
如果没有设置ro.sf.lcd_density的值，那么选择DENSITY_DEFAULT的默认定义；
再看DENSITY_DEFAULT定义处：
#
publicstatic final int DENSITY_LOW = 120;
#
publicstatic final int DENSITY_MEDIUM = 160;
#
publicstatic final int DENSITY_HIGH = 240;
#
publicstatic final int DENSITY_XHIGH = 320;
# publicstatic final int DENSITY_DEFAULT = DENSITY_MEDIUM;